Power transmission



March 13, 1951' D. B. GARDINER ETAL 4 POWER TRANSMISSION Fild Namh 12, 1949 2 Sheets-Sheet 1 INVENTORS DUNC-AN B. GARDINER ERNSTEKLESSIG ADOLF KEEL ATTORNEY March 13, 1951 D. B; GARDINER 'ETAL 2,544,988

POWER TRANSMISSION Fil ed March 12, 1949 2 she'ets sheet 2 INVENTORS DUNCAN B. GARDINER ERNSTEKLESSIG BY A DOLF KEEL ATTORNEY Patented Mar. 13, 1951 POWER? TRANSMISSION r'rDuncam B: Gardiner, Detroit, Ernst F. Kles'sig,

Berkley 'iandAdolf KeeLJ-lighland Park, Mich., assig-nors to 'Vickers Incorporated, Detroit, 'LMich; a corporation of Michigan App'lieation' March 12, 19.49.;2SeriaLN0. SL146 V ...11 Claims. .11 :This inventionrelates to power transmissions, .andtiszparticulalrly applicable towthose of the 2 type. comprising two. .or;;more.-fluid; pressure ::energyiitranslating..devices; oneiof -.which may cifunctionas a pump .andran'other asv a fluid motor. The invention relates, generally to; rotary fluid gipumps andrirr particular to. those of the vane aitype.

Onefl'of :.the:.:ma-jor :problems encountered in designing rotary pumpsnis .:.that of providing :proper clearance;- between thev rotor; faces, and afthe: surfacesuagainst {which they rotate. There should be a slight clearance in order ;for the rotor to runkfre'ely but; the clearanceshould not the. too high because-of decreasing the volumetric e- .eificiencycof the pump.fWhere the abutting sur- ;.afacesqarestationary,'ithewp'arts mustbe machined to very close tolerances; and in spite of maintaining closemanufacturing -.to1erances leakage will increase as the operating pressure increases .and' with changes in viscosity of. the .fluid medium. .One method for. maintaining proper rotor clearances is the; providing of. a floating; cheek plate and utilizingfluid pressure -from.-the soutlet side :of the pump against the cheek plate toadjust the clearance between therotor-and bearing sur- :faces. Ihis increases the costof-the pumpsomewhat because :of -1-intricate porting. and cooperativepassages which. mustebe provided in the castingof:.the-pump. i In-many cases;=because of the 1 cheek plate being mounted .on the. shaft,-sepa- :ratemeans must be,- provided to. overcome fricztionitendingto-prevent the bushing from properly functioning.

I It is an object of--.-thisinvention to-provide an improved; simplified, rotary: fluidi pump having a floatably mounted, pressure responsive 1 check ;plate for. maintaining properl rotor clearances. It is another-object ofthis invention to provide mane improved, simplified, low cost rotary vane pump. .This' .has :been-tacccmplished a. without sacrificing efiiciency by retaining basic pump- .-:ing elements well known in the art: and utilizing t-inz'combination therewith: a low cost. end'cap member --which cooper'ates -with a...sim plified casing member to reduce-thetotalnumben of rparts. formerly necessary. ..The endlmember is providedlvvithlan open recess which ..is closed. by amounting theend cap member againstthe pumping unit. .In this manner. a fluid delivery chameber. is-formed Which. lies immediately adjacent the pumping. elements and in--which. the...cheek plate may-be mounted.

. One feature of the, pump is the-advantage of having inlet passages completely. onaoneside of nthesroton of :theapumpinge; unitrwhile the 4 outlet passage is completely on'the othersidexgofjthe rotor. The. inlet passagesllead ldire'ctly. toithe suction .side...of.-the pumping I elements. andgthe outlet. passage is connected to the. fl'uid.-delivery 5 chamber. Thepheek plate. is provided ivlthldiial function porting, ,operatingi aslfluid' distributing ports inconnecting thedelivery side ofithe umping unit to. the outletand which also. directs. fluid pressure to the fluid delivery, chamber which. is

utilizedior..maintainingithe. cheek ..plate. ingfluid sealing .engagementagainstTthe"rotor.

.Another importantieature. oflthe, pumpislthe t-mountingof the drive shame. the catsingcompletely ion one. sideofethe .rotor,i'.thus obviatin the necessity of; ayhplurality .-offshaft..mounting whores which... must... be rconcentrica. and ,..in.-J strict axial ..alignment. Properly. spaced, combined radial and thrust. bearings-arehplaced. .inllthe casing memberwithin which the shaftismounted ,-.so as to m'ake-I-the.lattericapableuof receiving .thrust-andradial loadsbf gears fgc hainrpulley as drives and other various .drivingunits.

.One-of the mostimportantlieatures.. iof;the pump is thetprovision. oil a. .novel. cheek :plate -.adesigned ..to :cooperate in.- prov'iding. proper, rotor :rclearance. The cheekplateis centra1ly.imper -forateeand the-peripheral edge "ofi'the'jplate. is .--maintained against. aaportion ofha ,cam ring within-zwhich .therotor. is ..mounted. i'The rotor c-t-hick-ness isslightly. IessthanIIthatbf the cam ring to provideaaiclearance between. the. rotor and the cheek plate. .The entire opposite. suri ace of the cheek plate is. exposed to'jI fluid. pressure .in-v the delivery Tchainber. ii The cheekj plate is .constructedpf a. material .--and .so. designed as to permit a slight deflection toward. the. rotor uponincreasesof pressure inthe wdelivteryflchamber. Theline of vdeflection and amountthereof ..may be controlled fromthe modulus 'of elasticity 10f the. material selected by providing a thickness and shape of the plate to give the result desired. .In Jthis; manner a? tolerance for "'wear ,:may" be originally. provided for and: inaddition volumetric efficiency "offthe pumpjmaintained-"over a wide pressure range.

"It is thus another objectof "this invention to provide a simplified lowcost structure-"of'the aforementioned" type having certain advantages contributing to efficiency,reliability; "and-long life 0 .as well. as ease "or maintenance.

In the drawings:

Figure 1 is a sectional view of a preferred form of the present invention taken on line I-I of Figure 3.

Figure 2 is a planned view of the present invention.

Figure 3 is a view taken on line 33 of Figure 1.

Figure 4 is a fragmentary view of Figure 1 showin rotor clearance in exaggerated form.

Figure 5 is a view similar to that of Figure 4 but showing rotor clearance upon deflection of the cheek plate.

Figure 6 is a view taken on line 6-6 of Figure 1.

Figure 7 is a view taken on line 1-4 of Figure 1.

Referring to Figure 1 there is shown a rotary vane pump Ill comprisin a pumping unit indicated generally by the numeral l2 mounted between an inlet casing member l4 and an end cap member l6.

The pumping unit l2 comprises a cam ring l8 within which, as is shown in Figure 6, is mounted a hubless rotor 20 carrying vanes 22 which reciprocate in slots 24 and the ends of which are maintained by pressure fluid against the approximately oval shaped inner surface 26 of the cam ring [8 which forms a track for the vanes. With the rotor 28 mounted within the cam ring [8 two'opposing working chambers 28 and 30 are formed through which the vanes pass as the rotor turns. These chambers may be appropriately divided into fluid intake zones and fluid delivery -zones, the former or which comprise that portion of the chambers 28 and 3B registerin with inlet openings 32 of the casing member and the latter of which comprise that portion of the chambers registering with outlet openings 34 of a cheek plate 36 (Figure 7) fioatably mounted in the end cap 56. Referring to Figure 1, the rotor 26 is driven by a shaft 38 rotatably supported solely within the inlet casing member M by means of spaced apart, radial and thrust bearings 40 and 42. The pump is hydraulically balanced because the bearing loads imposed are cancelled .out by equal and opposing radial hydraulic thrust loads. The shaft 38 is operatively connection indicated by the numeral 44. The spline on the shaft fits the spline in the rotor with only a very small clearance so that the shaft acts as the locatin means for the rotor radially and yet permits'a slight amount of play for the rotor to take up a position flatly against the face of the casing member i4 even though it be not perfectly square with the shaft.

The casin member i4 is provided with an external inlet port 46 having a passage 48 leading directly therefrom to which is connected the inlet openings 32, the latter of which register with that portion of the working chambers 28 and 30 described as the fluid intake zones. An oil seal, indicated generally by the numeral 50, is provided to prevent shaft leakage.

The end cap member [6 is provided with an external outlet port 52 leadin directly to an open recess which is closed by the cam ring l8 and the rotor 26 to form a fluid delivery chamber and which, for the purposes of convenience, will be indicated generally by the numeral 54. The end cap member is and the casing member I4 are provided with fiat end Surfaces to cooperate with the opposing fiat mating surfaces of the pur. ping unit l2. As shown in Figure 2 the easing member l4 and the end cap member 16 are 'nected to the rotor 36 by means of a splined con- 4 connected to the cam ring 18 and to each other by means of suitable screws 56.

The cheek plate 36 is prevented from rotary movement by means of two dowel pins, which are indicated by the numerals 58, inserted through the cheek plate 36 and extending through the cam ring 16 into the casing member l4. The dowel pins also serve to provide accurate alignment means for changing the relative position of the pumping elements when the direction of shaft rotation is reversed. The outlet openings 34 of the cheek plate 36 extend completely through the plate and as the openings on one side of the plate register with the fluid delivery zones of the working chambers 28 and 30, fluid is pumped directly through the openings into the fluid delivery chamber 54.

The cheek plate 36 is adapted to be maintained in fluid sealing engagement against a portion of the cam ring 18 and the rotor 20 by means of fluid pressure in the fluid delivery chamber 54. Thus, the ports 34 of the cheek plate 36 serve a dual function. They connect the delivery side of the pump directly to the chamber 54, the latter of which is connected to the external delivery port 52. In this manner they function as pump delivery distributing ports and deliver pressure fluid to the chamber for maintaining the cheek plate against the pumping unit. A spring 60 maintains the cheek plate 36 against the cam ring l8 and the rotor 20 during standby or starting periods.

Pressure fluid from the outlet side of the pump is delivered to a groove 62 of the rotor 26 through a plurality of holes 64 extendin through the cheek plate 36. The slots 24 of the rotor 2|] within which the vanes reciprocate are mounted at their bottom ends as indicated by the numeral 66 and communicate with the groove 62. In this manner pressure fluid from the delivery chamber 54 is delivered through the cheek plate holes 64 to the rotor groove 62 and to the bottom of the slots 24 in order to maintain the outer ends of the vanes 22 in contact with the inner periphery 26 of the cam ring l8.

An inlet flange 68 and an outlet flange 16 may be suitably connected, respectively, to the casing member l4 and the outlet end cap member 16.

Suitable oil seals 12 and T4 are provided in the casing member [4 and end cap member l6 adapted to be on opposite sides of the cam ring I8 to aid in sealing the outlet from the inlet side of the pump and to prevent seepage.

The inlet casing member 14 is provided with a fiat end surface indicated by the numeral 16 which serves as an end wall adapted to cooperate with the flat mating surfaces of the cam ring l8 and rotor 20. The end cap member 16 is also provided with a hat surface at the open recess end thereof indicated by the numeral 18 which cooperates with the opposing flat mating surfaces of the cam ring l8 and rotor 26. The check plate 36 is designed to fit in the delivery chamber 54 so as to prevent leakage with the cooperation of the seal 14.

The entire surface of the cheek plate opposite to that facing the cam ring 18 and rotor 29, and indicated by the numeral 86, is exposed to outlet pressure in the delivery chamber 54, in order to maintain the cheek plate in fluid sealing engagement against the cam ring and rotor. Running clearance between the rotor 20 and the surface of the cheek plate 36 facing the rotor 20, said surface being indicated by the numeral 82, is provided by the difference in thickness between ausa e "the cam ring and that'of therotor. irhe amount or running clearance is dependent: u-porr theadesigrrbf the'cheek plateand the material of which it-=is cnstr'ucted :but" 's on the-order 'oi a thou- -'sole supportagai-nst rightward movement-is that provided by: a portion "or the :cam ring l B against i which the peripheral edge :of -thea'cheek: plate -is f orcd f bypressure fiuid -in -delivery chamber. "The remainder: oi the cheek plate is entirely11nsuppQrted -agaifiSt' r ightward axial: movement-be- "cause ofthe 'clearanceiprovided b'etweenLtherotor and the cheek platazlsaidclearance beingishown -in g-rea'tly exagg'erated iform in Ei'gILre i-A. l The cheek -p1ate 36iscomprisedor a material such as castr i-rongaluminum-allover hronze; andis1"designed to provide" a: predetermined deflection "of i itsunsupported surface as a? function-bfithelpressure existent iati-the outlet" i side -of: thetpumping cunit. The li-ne of-deflection and: amount thereof may: be accurately controlled: by designing: ;the sha pe and thickness of the plate in'zrelation tozthe ttyrze -caf material of whichthe plateis constrn'cted and: consideringralsoithessize" ofnthe' pumpzland i-theqiriessurestowhich; it fwill be' subjected. 5:. The modulus of elasticity of different materialsyxsuch -:;as=:castriron; which thetcheekiplate of. thepresent ziinventionais preferably: constructed because-of its low c'ost-, -is tknown and the lineof andamount of and'efiectionrzmayi-cber controlled by :designing the ijplate :toarneet any: application, Thus, theathickrness of thexplateais: determined to acertain extentfi upon the :original: clearance-between the l-rotorand theplate. Theilarger thev clearance,

the thinner .the;plate: will' be made to provide for moredeflection.

The volumetric: efiiciency:.-of the pump" may be nicoritrolled Joyadetermining. the thickness of the plate inr'elation to the clearance. i Thus, the volumetric refiiciencyiofj pumpsuoperating over a wide .ipressure' rangemay be maintained substantially constant .by-=slightly-increasing the rotor oleara-nceand-utilizing a slightly :thinner'iplate. :Fige Y ure 5v illustrates-deflection of the cheek: plate -36 caused I by increased operating pressure,-v the Y rotor clearance ofwhich has been-greatly exaggerated for purposes of illustration.

When the desired direction :of rotation of the i drive -sha-it-38 is to be reversed, the cam ring 12 wand rotor 18- together with thehvanes '22. are turned over end for end so that-screw holes: 82, i 84, 86-;and-=88 in the: cam ringl8 which formerly registered, respectively,withsorew holes 90;92, SA -and '96s in vthe casing member 14 register; -respectively, with the casing holes 92,? 90,:-9 6,: and -94. i- Thedowel pins Bik -Which are located-on a diameter 45* :from thezaxes of: the cam-ellipse, accurately align the pumping elementsrso that the -inlet openings --32 of the. casinglmember and .the outlet: ports 34 of thecheek plateregister, respectively, i with the fluid. intake and fluid sdelivery zones-of the pumping chambers 28 and 30. 7; They :also prevent errors in reassembly when shaft .rotation is to lie-reversed. However, theyarernot -essential for preventing errors in reassembly. when analternate form of construction such as is shown -indotted-lines in- Figure 6 is utilized. 'Whereintersecting linesdrawn from the axis of the holes '82, 434, 86, and 88. cform a square; it. is .lpreferredlthatrthe dowel-pins be utilized to'wprevent errors in reassembly" when reversing? rotation whi'chvwouldlincorrectly displace :the major axis of the cam ring recess 26. Whe1-e,-:.however, "the location of the holes in the cam ring, :oasing m mber, and end-oapmemben-are; as shown in t6 dottednines; rin riigure .6; heeidmrectanguIarTdationsh ip; then the: screwsz-fifizwilleserve"zthei dual fun ctioriifiofinot ionly connctingfthezcasing mem- -b'er, cami ringa andiendifcap membefitogether'; but

' 5 also will prevent errors in reassemblybfitharhe'mbers. Likewise, the' screws mayrbeilocatedzfat the corners:oflassquarepbutmhe outline of rther'cam rillg casingfi memben'iandijendr capi'may :bamade o'avoid'zsuch errors."fThezimportantrequirement is only ith'at'-i the r aligning (means,- such iiasi-zthe cldowelsgtheiscrewsyorzitherbo'dyr outlines beiisym- -metrically5dispbsed aboutag'fdiaineter 4'53. fromzthe '2 bers i2 8- and-30. nest"'the roto turns xthe vanes will marry the: fiuidithroughfithefiworkingichambers! 8: and i it to thet'fiuid delivery "zones zth ereof where-it avillhe deliver dathrough therdeliv- -I'eryzports -34-= of the: chee late'to the Hide de- 1 2 liveryiichamber 54 :a :and'iithence IitO the eoutlet port 52. r

'The enti rei 'suriacelmflfi the cheek; plate 36 is exposed-tdfiuid pressure ri ztheidelivery'ichamloer 54to' maintain proper rotorcl'earance.

As shown in: exaggeratedeformzin- Eigurez'fihe outer-periphery or cheek "plat-e Mmvill beimaintained' in fluid: sealing:"errgagem'ent? against; a ''portion' ofthe' 0am: ringl l 8. Theiioriginali rotor x f clearance remains; undisturbed; at 310w pressures. =However, as the lpre'ssurei at-L'the' outletlportiT52 incre'ases the: '-corresponding .i-ncreases: iof'iipressure in the 'delively chambel' ih'alcfihg over. :the rremainingiiunsupportedi suriace 011011 the-.1 cheek wpla'te' GBAWilLidefiectAthe cheek-plate:towarddzhe rotor asshowniintEigure 5a and reduceithelrotor clearancer Due to theafa ct vthatLthe ehtiresurfaceftfll isrex- .z p'osed'ito pressure: l in itheudeliveryi ohamberGM whi1e 1 the?-:surfaoe iacing the'firOt-or is exposed 4s-not on1yto delivery pressure butzalsoiinlet pres surepa' 'difiere'ntiallbf .fo'r'cesak establishedfhighly in iavor' of those acting' on the surracesso. .;:';As the pressure increasesdin thexdeliveryificham ber =541the4dflctiom ofithe'i cheek "platens; increased 1to r further adecr'ease Tithe .irotor nclearfanee and :Imaintain' volumetric \eiiiciencylof:v the pump.

:Therel isfihuszprovidedra vane pumpiwhichzis "lnot' ronlyrmore efficient: than: predecessors of this --:type, but e-"which :ihas ebeen s greatlyr' ireducedixin cost. The construction obviates the: necessity-of .ihavingit bearingaplateszonzrboth: :sides' Tofn the :ro-

:tor. It eliminates the nec'essity of vmountingithe ---..cheek plate'on the shaftorxot DI'OVidlIlglIIOllI'lt- "ing' bearings thereior to' prevent loss: of efiicienoy .:due .tozfriction. The low-cost end member: permits' mountingvofzthei cheekspl-atelin1a -:c-ham wber-convenientlygadjacent-totthe rotor. ;:The.-;end cap :imember is easily: removable: for replace- -m ent. 10f a: new -oheelgplate and -in addition-.-the 5 casin member and :end "cap member may serve #continuallywith replacement-pumpingle1ements, namely,thecam ring, rotor,-and vanes.

, The construction I alsowpermitsrthe v inletwpassages being on one=-si-de=of the -:rot0rand-l-;leiadingrrdirectly -.to.ithe fiuid intake-.i zones-pf the mpumpi-ng -unit while theilId-ualfunction": out1et v-portingin-lthe cheek plate :diE-BCHYCOHDQGt-Sfihfl fluid delivery zones of the pumping unit and the d liv r :chamber ito-theoutlet; passageion the ,0pposite sideof theretor. l

ectang ularg aszshowri inidottedzlineseirirEigure-fi,

- pletely on one side of the pumping mechanism and leading to the fluid inlet zone, an end member having an'open recess and an outlet passage connected thereto and mounted against the housing on the other side of the pumping mechanism to close the recess and form a fluid delivery chamber, and a centrally imperforate cheek plate floatably mounted in the fluid delivery chamber and having an outlet opening extending therethrough registerin with the fluid outlet zone, said cheek plate being maintained in fluid sealing engagement against the pumping mechanism by fluid pressure in the delivery chamber delivered thereto through the cheek plate outlet opening.

2. A rotary vane pump comprising a housing having a pumping chamber, a slotted rotor carrying a plurality of substantially radially movable vanes and mounted in the chamber to form a fluid intake zone and a fluid outlet zone through which the vanes move a the rotor turns, an inlet passage in the housing completely on one side of the rotor and leadin directly to the fluid intake zone; an end member having an open recess and an outlet passage connected thereto and mounted against the housing on the opposite side of the rotor to close the recess and form a fluid delivery chamber immediately adjacent the rotor, a pressure responsive, centrally imperforate, cheek plate floatably mounted in the fluid delivery chamber and havin an outlet opening extending therethrough registering with the fluid outlet zone, said check plate being maintained in fluid sealing engagement against therotor by fluid pressure in the delivery chamber delivered thereto through the cheek plate outlet opening.

3. In a rotary vane pump, the combination of a housing having a pumping recess, a slotted rotor carrying a plurality of substantially radially movable vanes and mounted in the recess to form a fluid intake zone and a fluid delivery zone through which the vanes move as the rotor turns, an inlet passage and an outlet passage in the housing respectively connected to the fluid inlet zone and the fluid delivery zone, means forming a rigid abutment at one side of the rotor, an elastic, deflectable cheek plate floatably mounted in the recess immediately adjacent the other side of rotor, porting means connecting the fluid delivery zone to the recess on the side of the cheek plate opposite to that facing the rotor, and a rigid shoulder supporting the outer peripheral portion of the cheek plate against the fluid pressure force on said opposite side and forming a running clearance between the rotor and the unsupported surface of the cheek plate facing the rotor, said unsupported surface of the cheek plate being deflected towards the rotor for reducin the running clearance in response to increases of delivery pressure of the pump. 7

4. In a rotary vane pump, the combination of a. housing having a pumping recess, a slotted rotor carrying a plurality of substantially radially movable vanes and mounted in the recess to form a fluid intake zone and a fluid delivery zone through which the vanes move as the rotor turns, an inlet passage and an outlet passage in the housing respectively connected to the fluid inlet zone and the fluid delivery zone, means forming a rigid abutment at one side of the rotor, an elastic, deflectable cheek plate floatably mounted in the recess immediately adjacent the other side of rotor, porting means connecting the fluid delivery zone to the recess on the side of the cheek plate opposite to that facing the rotor, and a rigid shoulder supporting the outer peripheral portion of thecheek plate against the fluid pressure force on said opposite side and forming a running clearance between the rotor and the unsupported surface of the cheek plate facing the rotor, said check plate being comprised of a material, the thickness of which is determined by the modulus of elasticity of the material to provide a predetermined deflection of the unsupported surface of the cheek plate towards the rotor for reducing the runnin clearance in response to increases of delivery pressure of the pump.

5. In a rotary vane pump, the combination of a housing having a pumping recess, a slotted rotor carrying a plurality of substantially radially movable vanes and mounted in the recess to form a fluid intake zone and a fluid delivery zone through which the vanes move as the rotor turns, an inlet passage and an outlet passage in the housing respectively connected to the fluid inlet'zone and the fluid delivery zone, mean forming a rigid abutment at one side of the rotor, a centrally imperforate elastic, deflectable cheek plate floatably mounted in the recess immediately adjacent the other side of rotor, porting means in the cheek plate connecting the fluid delivery zone to the recess on the side of the cheek plate opposite to that facing the rotor, and a rigid shoulder supporting the outer peripheral portion of the cheek plate against the fluid pressure force on said opposite side and forming a running clearance between the rotor and the unsupported surface of the cheek plate facing the rotor, said unsupported surface of the cheek plate being deflected towards the rotor for reducing the running clearance in response to increases of delivery pressure of the pump.

6. in a rotary pump, the combination of a housing having a pumping chamber, pumping mechanism mounted in the chamber including means forming a fluid inlet zone and a fluid outlet zone, an inlet passage in the housing completely on one side of the pumpin mechanism and leading to the fluid inlet zone, an end memher having an open recess and an outlet passage connected thereto and mounted against the housing on the other side of the pumping mechanism to close the recess and form a fluid delivery chambar, a cheek plate floatably mounted in the fluid delivery chamber, porting means connecting the fluid outlet zone to the delivery chamber on the side of the cheek plate opposite to that facing the pumping mechanism, said cheek plate being maintained in fluid sealing engagement against the pumping mechanism by fluid pressure in the fluid delivery chamber, and a drive shaft operatively connected to the pumping mechanism mounted and rotatably supported in the housing completely on the inlet side of the pumping mechanism.

7. In a rotary pump, the combination of a housing member having a pumping recess, pumping mechanism including a rotor mounted in the recess and forming a fluid intake zone and a fluid delivery zone, an inlet passage on one side of the rotor leading directly to the fluid intake zone, an end member having an outlet passage and mounted against said housing member on the opposite side of the rotor to close the recess and form a fluid delivery chamber immediately adjacent the rotor, said housing providing a rigid abutment at one side of the rotor, an elastic deflectable cheek plate floatably mounted in the delivery chamber at the other side of the rotor, porting means connecting the fluid delivery zone to the delivery chamber on the side of the cheek plate oppostie to that facing the rotor, a rigid shoulder supporting the outer peripheral portion of the cheek plate against the force of fluid pressure in the delivery chamber and forming a running clearance between the unsupported face of the cheek plate and the rotor, said unsupported surface of the cheek plate being deflected towards the rotor for reducing the running clearance in response to increases of delivery pressure of the pump, and a drive shaft operatively connected to the rotor and rotatably supported in the housing completely on one side of the rotor.

8. A rotary vane pump comprising a slotted rotor carrying a plurality of substantially radially movable vanes, a cam ring of generally elliptical inner contour surrounding the rotor to form diametrically opposite pairs of fluid intake zones and fluid delivery zones through which the vanes move as the rotor turns, a pair of housing members, one having means providing a single pair of inlet openings adjacent an end face of the rotor and ring and extending arcuately along said intake zones and the other member having a chamber adjacent the opposite end face of the rotor and ring, said one housing member having an external inlet port in communication with said inlet openings, said other housing member having an external outlet port communicating with said chamber and a floating side plate in said chamber normally contacting the ring and rotor, said plate having a single pair of outlet openings therethrough extending arcuately along said outlet zones.

9. A rotary vane pump comprising a slotted rotor carrying a plurality of substantially radially movable vanes, a cam ring of non-circular inner contour surrounding the rotor to form equally spaced sets of fluid intake zones and fluid delivery zones through which the vanes move as the rotor turns, a pair of housing members, one having means providing inlet openings adjacent an end face of the rotor and ring and extending arcuately along said intake zones and the other member having a chamber adjacent the opposite end face of the rotor and ring, said one housing member having an external inlet port in communication with said inlet openings, said other housing member having an external outlet port communicating with said chamber and a floating side plate in said chamber normally contacting the ring and rotor and having outlet openings therethrough extending arcuately along said outlet zones.

10. A rotary vane pump comprising a central pumping unit having parallel plane sides and including a stationary outer ring and an inner, vane-carrying rotor, together providing a plurality of fluid intake zones and a plurality of fluid delivery zones, a main base member abutting one side of the unit and comprising a thick block having only inlet passages therein and a shaft connected with the rotor and journaled in said block, a housing member secured to the opposite side of the pumping unit and having a fluid outlet connection and a chamber enclosing the rotor and a portion of the face of the ring, a floating cheek plate mounted in the chamber to abut the face of the rotor and ring, and outlet ports formed in the cheek plate to carry the entire fluid delivery from the pumping unit, through the chamber and into the outlet, said block providing a rigid base with a plane face which is relatively free from distortion under fluid pressure loads and against which the cheek plate may urge the rotor and vanes under the pressure of the fluid being delivered through said chamber.

11. A rotary vane pump comprising a central pumping unit having parallel plane sides and including a stationary outer ring and an inner, vane-carrying rotor, together providing a plurality of fluid intake zones and a plurality of fluid delivery zones, a main base member abutting one side of the unit and comprising a thick block of solid metal having a single axial bore forming a shaft journal mounting, a single transverse bore forming an inlet connection and having perpendicular branches extending to said intake zones, and a shaft connected with the rotor and journaled in said block, a housing member secured to the opposite side of the pumping unit and having a fluid outlet connection and a chamber enclosing the rotor and a portion of the face of the ring, a floating cheek plate mounted in the chamber to abut the face of the rotor and ring, and outlet ports formed in the cheek plate to carry the entire fluid delivery from the pumping unit, through the chamber and into the outlet, said block providing a rigid base with a plane face which is relatively free from distortion under fluid pressure loads and against which the cheek plate may urge the rotor and vanes under the pressure of the fluid being delivered through said chamber.

DUNCAN B. GARDINER.

ERNST F. KLESSIG. ADOLF KEEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Date Number Name 715,722 Womer Dec. 9, 1902 904,781 Hoard et al Nov. 24, 1908 994,392 Hauer June 6, 1911 1,010,956 Read et al Dec. 5, 1911 1,590,384 Kucher June 29, 1926 1,635,522 Wilson July 12, 1927 2,037,894 Grisell Apr. 21, 1936 2,141,170 Centervall Dec. 20, 1938 2,312,891 Ferris Mar. 2, 1943 2,335,284 Kendrick Nov. 30, 1943 2,384,872 Baker et al Sept. 18, 1945 2,393,223 Rosen Jan. 15, 1946 2,462,732 Dusevoir Feb. 22, 1949 FOREIGN PATENTS Number Country Date 11,818 Great Britain 1910 233,064 Great Britain May 7, 1925 274,041 Great Britain Oct. 27, 1927 

